Ceilings, walls and truss clips

OK, i've read many threads about this and am still confused. I've got 36' (9/12 pitch)and 58' (4/12 "shed roof" pitches on both ends with 9/12 pitch in between) trusses with about a third of the 58' trusses having a interior bearing wall at about 26' in. Top and bottom chords are 2X6. I think the bearing walls are all pretty level. I was told the truss manufacturer had put in a little camber (or arch or whatever it's officially known as) in the bottom chords. I guess this is why the 58 footers over the bearing wall are standing off it about 3/4" (no measurement, just guess). All trusses are tied on both ends with H-1 clips to a double top plate (the bottom top plate bolted to ICF concrete and top top screwed down to it) and toe-nailed (five 16d nails each) to interior bearing wall top plates.

First question: On that interior bearing wall (garage), should I pull the toe-nails and install truss uplift clips instead?

Second question concerns interior wall/ceiling "connections". With these trusses and here in the Ozarks I plan on using truss clips on all interior non-bearing wall top plates perpendicular to bottom chords. The ceilings are to be pine or cedar T & G 1X6 or 8 attached to bottom chords with "plastic" barrier in between. What's the best way to handle the wall/ceiling interface? I could put blocking between the bottom chords for parallel walls and nail the ceiling boards completely to the bottom chords, but it seems I may look up some seasons and see a one or two inch gap and plastic. If I put up ceiling before ANY interior non-bearing walls, I still have gaps but wouldn't see plastic sheeting. Still, putting in those clips thru a finished ceiling would be a real hassle (I suppose -- haven't given too much thought to how on that...). If I attach a 2X6 nailer to top plates, would the boards take that much deflection (no nails in bottom chord within 16" of wall nor in that top plate "nailer")? And, in that case, if that part of the ceiling deflects down with uplift, what about the part that is parallel and next to the wall that is perpendicular to the bottom chords? -- keeping nails away from the wall for three board widths seems tedious at best (floating furring strips above for those?).

I lean toward the option of installing the ceiling before raising any walls but still am stumped on how to attach the clips. Assuming it could be done, I suppose some kind of molding attached only to the ceiling could "hide" the seasonal gap as it would move up and down the wall without being attached. I hope some of you have stuck with me thru all this rambling and decipher what i'm trying to picture in my mind. I really feel frustrated with all this. I want to do it right.

(post #97061, reply #1 of 10)

It depends. Were the trusses DESIGNED to use the bearing wall? If so, there should be no problem nailing the trusses down to it. If they were designed to be clear spanbut the wall just happens to be there, they should NOT be fastened to the wall.

My only reservation is that I would suggest shimming under the trusses rather than pulling them down to the wall.

"The ceilings are to be pine or cedar T & G 1X6 or 8 attached to bottom chords with "plastic" barrier in between. "

Never seen a house done that way. Are you sure your local codes will allow you to NOT have drywall? (For fire resistance)

I think you could still "float" the corners just like with a drywall ceiling. But you might have to hold the nails farther back than 16".

"...what about the part that is parallel and next to the wall that is perpendicular to the bottom chords? -- keeping nails away from the wall for three board widths seems tedious at best..."

That does sound tedious. But it also sounds like what needs done. Don't know how you'd get around that.

(post #97061, reply #2 of 10)

I have no idea what the plastic detailing is all about Boss, but I do know about framing with trusses.

The backing on parallel walls will hold the ceiling...

If there is concern about truss uplift, then I would put 22.5" blocks (2x6) between the trusses on all perpindicular walls.

blue

Just because you can, doesn't mean you should!

Warning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. According to him I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!

"...

keep looking for customers who want to hire YOU.. all the rest are looking for commodities.. are you a commodity ?... if you get sucked into "free estimates" and "soliciting bids"... then you are a commodity... if your operation is set up to compete as a commodity, then have at it..... but be prepared to keep your margins low and your overhead high...."

(post #97061, reply #4 of 10)

Thanks, guys. The trusses over the wall ARE designed for it so I'll definitely shim. (Why didn't I think of that! -- hmmm, no need to answer that....) The "plastic" IS for vapor barrier but not sure what material will actually wind up being used for that vb. Bldg inspectors are ok with T & G boards without drywalling first. I suppose if the wood ceiling catches fire, a drywall layer probably wouldn't save the trusses anyway. Now, for the uplift prob... what would be wrong with doing the ceiling first and then not attaching the interior stud walls at all when they go up?

(post #97061, reply #5 of 10)

Rick, the only reason that the interior walls are attached, is to keep them straight until it's boarded. There is no structural necessity for anchoring the interior partitions to the trusses. You will have to figure out how to keep them from falling over.

blue

Just because you can, doesn't mean you should!

Warning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. According to him I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!

"...

keep looking for customers who want to hire YOU.. all the rest are looking for commodities.. are you a commodity ?... if you get sucked into "free estimates" and "soliciting bids"... then you are a commodity... if your operation is set up to compete as a commodity, then have at it..... but be prepared to keep your margins low and your overhead high...."

(post #97061, reply #7 of 10)

Boss- I've just gotten involved with a new venture, looking for a little input and hope that you might be kind enough to help.

I've worked on houses in the North for about 30 years, some new construction, some renovations. Now, I'm going down South, to Virginia, and come across a nice new (1978) Church building being sold by the Congregation. I look at the open floor plan, existing utilities and so on and conclude it would be great for a rental or resale. As I am doing the measurements for my future partition walls, it occurs to me the ceiling is sort of cathedraled and I think there's probably trusses up there. Sticking my head in the attic confirms this. Does me no good, I'm used to stick built.

I read somewhere that there is a problem with nailing the top plate of the new stud walls to the bottom of the trusses, because the trusses will move and there will eventually be a gap between the two. Any suggestions?

A couple of measurements/details - building is 30 feet wide. Ceilings angle from the tops of the walls up about a third of the way in on both sides, then there's a horizontal member that connects the two sides. It's in the middle third of the roof. It's a finished ceiling, sheetrock, so I don't know if the horizontal member was part of the truss design or not. Nobody knows where the plans are for this building to find out any details. Ceiling height (thankfully) at the flat part is a little less than 10 foot. Not a steep pitch, maybe 4/12 tops . I'm dividing it into four bedrooms and two baths, sort of center hallway so most of the top of the hallway wall will be under the "flat" part of the ceiling.

(post #97061, reply #9 of 10)

I just tried the three links that were in that thread. None of the three worked - no pages - whatever. I will see is I can locate something elsewhere in either Trussnet or woodtruss, hopefully under a different name. Thanks. (By the way thanks for the old thread about the Spec house from hell. I will probably start one later this year, 1600 square feet. Your experiences are good warnings.)

Glad to hear the "Spec house from hell" was entertaining for you. Don't know if you've followed the story - I see you haven't been around BT too long - We ended up moving into the house last summer. It never did sell.